Duct device



Oct. 15, 1968 L. HARPER 3, 5,737

DUCT DEVICE Filed May 5, 1965 INVENTOR. LAFFtE HARPER MWw ATTORNEYS United States Patent 3,405,737 DUCT DEVICE Latlie Harper, 1192 Montgomery Ave, San Bruno, Calif. 94066 Filed May 3, 1965, Ser. No. 452,673 6 Claims. (Cl. 138-39) ABSTRACT OF THE DISCLOSURE A rail of sheet metal having a single central row of spaced pairs of projections bent therefrom to one side thereof each formed with a slot to respectively receive one of the ends of the blades of a double air turning vane, and a bridge on each vane between the slots of each pair to project into the space between the blades for bending over the vane along a slot of each pair to secure the vane to each blade.

This invention relates generally to improvements in air ducts and conduits, and more specifically to the rails and vanes that are used in the corners or turns of the conduits.

In air ducts and conduits such, for example, as are used in air conditioning units, it is common to use an assembly of elongated vanes in parallel, side-by-side, spaced relation within the elbows or turns. These vanes may be in a row, which row extends between the corners of the elbow, and their ends are secured to opposedly facing rails that, in turn, are secured to opposite sides of a conduit. The cross-sectional contour of each vane is arcuate with its concave side facing the inside corner of the conduit, such as shown in US. Patent No. 2,861,597 to M. M. Gracer.

Heretorfore, as shown in said patent, vanes may each be single or double. In the double vanes, as shown in my copending application Ser. No. 442,689, filed Mar. 25, 1965, each vane consists of two metal strips or blades connected along their longitudinally extending edges, both blades being bowed transversely thereof. The inner blade of each double vane, which is the blade having its concave side facing the inner corner of the elbow of a conduit when the double vane is within the latter, has a flatter or more shallow cross-sectional curvature than the other, or outer blade.

The pair of rails between which the vanes extend, and to which the ends of the vanes are secured, are strips of sheet metal. Heretofore these strips have been punched along a pair of parallel rows extending longitudinally of the rails to provide slots into which the end edges of a single bladed vane, or the end edges of the inner blade only of the pair of blades of a double vane extends. The material along the edges of each slot is protruded to the side of each rail that faces into the space between the rails, and when the end edges of each vane extend into the slots, the portion of each end edge so extending through each slot to the outer side of each vane is bent over the marginal portion of each rail along an edge of each slot to secure each end of a vane to each rail. A manually operated hand hammer is usually used to so bend the blade.

Heretofore the slots that receive the vanes are straight, with the slots along opposite marginal portions of a rail extending angularly relative to each other to intersect along a medial line extending longitudinally of each rail. As already mentioned, the inner blade of a double vane, which is the blade nearest the inside corner, is relatively flat, particularly along the longitudinally extending marginal portions of the inner blade, hence the curved end edges of the vanes are forced into straight slots and then secured to the rails in the manner already described. Noth- 3,405,737 Patented Oct. 15, 1968 ing secures the other and more arcuately curved outer blade to the rails.

The present invention is particularly concerned with the securement of double vanes to the rails, and at least one pair of adjacent slots is formed in each rail for receiving the end edges of the inner and outer blades of each double vane. The edge of one slot of each adjacent pair substantially follows the curvature of the convexly curved surface of the outer vane while one edge of the other slot of each adjacent pair thereof is adapted to substantially follow the curvature of the concavely curved surface of the inner vane. These curvatures of said edges of the slots are different, and furthermore, in the present invention, the portion of each rail between the slots of each pair projects a substantial distance between the blades of each vane, while the ends of the slots are approximately coplanar with the respective rails, thus providing a substantial portion of each blade for bending over the outer sides of the rails along one of the slots for securing the vanes to the rails.

One of the objects of the invention is the provision of a rail having the above general structure for the securement of double vanes thereto, and to the combination of a rail and double vane after securement of the vane to the rail, and in which structure, one or two rows of slots in each rail may be provided according to the size of the vanes.

Another object of the invention is the provision of rails requiring only a single, central row of slots in each rail adapted to secure both blades of double vanes to each rail.

A still *further object of the invention is the provision of an assembly of double vanes and rails that is more economical to make than heretofore, and more rigid.

Other objects and advantages will appear in the description and in the drawings.

In the drawings FIG. 1 is a fragmentary view of the side of a rail to which a double vane is to be secured.

FIG. 2 is a fragmentary view of the opposite side of the rail shown in FIG. 1 but to which an end of a double vane has been secured.

FIG. 3 is a view similar to that of FIG. 1 but with the double vane secured thereto and shown in cross section.

FIG. 4 is a cross-sectional view taken along line 4-4 of FIG. 3.

FIG. 5 is a reduced size, horizontal, cross-sectional view of an assembly of double vanes on a rail and secured in an elbow of a conduit or air duct.

FIG. 6 shows a modification of the invention shown in FIGS. 1 to 5 as applied to a relatively large vane.

In the drawings, with the exception of FIG. 5, only one end of one double vane will be shown, and only the portion of one rail to which said one end of the double vane is secured, or is to be secured. It is understood that the same structure is used for each end of each double vane.

A rail, generally designated 1 (FIG. 5) extends across each of the opposite ends of the double vanes, whether one or more of such vanes are used, and each rail is in the form of a sheet metal strip adapted to extend between the inner corner 2 and the outer corner 3 (FIG. 5) of an elbow in a conduit and the rails of each pair are secured flat against the opposedly facing sides of the elbow. FIG. 5 shows a row of double vanes, each generally designated 4, and which row extends between said corners 2, 3.

Each vane 4 comprises an inner blade 5 and an outer blade 6. Said blades are normally formed by a pair of strips of sheet metal of the same width and length. Blades 5, 6 are each arcuately curved to the same side in crosssectional contour with the opposite marginal portions of the inner blade 5 bent over the portion of the blade adjacent thereto and over the marginal portion of the outer 3 blade (FIG. 3) so that the outer blade will have a more sharply arcuate contour than the inner blade and the spacing between the blades will be progressively greater in directions from their longitudinally extending edges toward medial, longitudinally extending lines on the blades.

In the assembly of the blades and rails (FIG. 5) the convex outer surface of the outer blade of each vane will face toward the outer corner 3 of the elbow, and the concave outer side of the inner blade 5 will face toward the inner corner 2 of the elbow.

Each rail 1 of FIGS. 1-5 is formed with a central row of slots, which row extends longitudinally of each rail and parallel with the parallel opposite side edges 7 of the rail, and these slots are arranged in separate pairs, with the respective slots in each pair designated 8, 9 (FIG. 1) and the pairs of slots are spaced from each other a distance equal to the spacing between vanes 4.

The spacing between the slots of each pair is equal to substantially the maximum spacing between the blades 5, 6 of each vane, which maximum spacing is midway between the longitudinally extending side edges of each vane. The portion of the rail between each pair of slots 5, 6 is designated 10 and may be called a bridge.

The slot 8 of each pair is relatively narrow compared with the width of slot 9 and is adapted to receive the end edge of the inner blade 5 of a vane 4 (FIG. 3) while slot 9 is to receive the end edge of the outer blade 6.

One edge 13 of slot 8 (FIG. 4) is the edge that is adapted to substantially fit against the concave outer surface of the inner blade 5 while the edge 14 of slot 8 is at the opposite side of vane 4 when the vane is secured to the rail.

The edge 15 of slot 9 is the one nearest to slot 8 and is adapted to be positioned between the blades 5, 6 and ad jacent to blade 6 while the opposite edge 16 of slot 9 is adapted to engage the convex curved outer surface of outer blade 6 when the blade is secured to the rail.

No material of the rail is removed from the latter in forming the slots, but instead, the latter are formed by forcing the metal to the side of each rail that will face the other rail, and piercing the metal with slot forming elements, which elements break through the metal to form the slots. The ends of the slots are substantially coplanar with the fiat surface of the rail extending outwardly away from said ends, hence when the end edges of the blades 5, 6 are in slots 8, 9, the portions of said end edges extending outwardly of the ends of the slots will be substantially in engagement with said flat surface.

The marginal portion 17 (FIG. 4) of the rail along edge 13 of slot 8 curves away from the plane of the rail a substantial distance, which may be approximately of an inch in a vane that is approximately 2% inches wide, and the bridge 10 itself may project approximately of an inch along edge 14 of slot 8. The edge 13 of slot 8 is slightly convexly curved, linearly, between its ends, and edge 14 is slightly concavely curved, linearly thereof to substantially follow the convex surface of the inner blade 5. The level of edge 14, except at its ends, is approximately the same level as the marginal portion 18 of the bridge 10 that is adjacent to edge 14.

The marginal portion 19 of the bridge along edge 15 curves away from the plane of the rail, to the same side of said plane as bridge 10, a distance that may be approximately of an inch, while the edge 16 may project only approximately of an inch. Said edge 16 is concavely curved, linearly thereof to substantially follow and engage the concavely curved surface of the outer blade 6 that is centrally spaced between the side edges of the blade 6.

When the end edges of the blades 5, 6 of a vane are inserted into the slots 8, 9, the portions 20, 21 of said blades 5, 6 that extend from the plane of the rail to the edges 14, 16 are respectively hammered over the marginal portion of bridge 10 along edge 14, and over the marginal portion 24 along edge 16, at the side of the rail opposite to the side from which the vane 4 extends (FIGS. 2, 4).

This provides a rigid connection between the ends of the vanes and the rail, and the relatively narrow section 25 of each rail extending between the pairs of slots (FIG. 3) and which is substantially equal in width to the lengths of the slots, the latter being substantially equal in length, is slightly bowed transversely of the length of each rail to contribute to the rigidity of each rail. The rails may be wider than the widths of the vanes, in which case the marginal portions may be bent longitudinally of the rails to form reinforcing ribs 26, or the rails may be narrower than the width of the blades. The fact that the single row of slots is centrally between the side edges of the rails enables a much wider variation than where two rows of slots are provided.

In the modification shown in FIG. 6, the slots would be arranged in a pair of rows equally spaced from a medial line extending longitudinally of each rail, but here again the slots are arranged in pairs in each row that structurally corresponds to the structure shown in FIGS. 1-5 except that the double vane, generally designated 32, is relatively wide as compared with the vanes in FIGS. l-S, and the slots extend at angles relative to said line that substantially correspond to the direction of the blades of the vane.

The rail in FIG. 6 is generally designated 31, and the vane is generally designated 32. Blade 33 is the inner blade of the vane and blade 34 the outer vane. These blades may be double or more the width of the vanes 5, 6 and are conventional.

Bridges 35 between the blades 33, 34 project into the space between the vanes the same as bridge 10, except that bridges 35 are spaced at opposite sides of the center line.

It is pertinent to note that slot 36 of each pair, in which the end edge of blade 34 is positioned, has edge 37 that substantially corresponds in curvature to the convex outer surface of blade 34 at said slot, and the edge 38 of the other slot of each pair substantially corresponds to the curvature of the convex inner surface of blade 33.

The end marginal portions of the blades 33, 34 that project through the slots are bent over the adjacent portions of the rail in the same manner as shown in FIGS. 2 and 4, thus providing better securement than where only one blade of a large double vane is secured at its ends to the rails.

Although the invention as disclosed in the drawings has been described in detail, it is to be understood that various modifications may be made in construction and arrangement within the scope of the invention as defined in the appended claims.

I claim:

1. A rail for securement to each end of a double vane of the type formed from two strips having parallel longitudinally extending edges secured together with the strips similarly curved transversely thereof about different arcs providing an inner blade and an outer blade spaced apart between said edges, and having their end edges at each end of the double vane in a plane that is substantially normal to the length of the vane, which rail comprises;

(a) a sheet of metal formed with a row of slots arranged in pairs spaced apart longitudinally of said row with the slots of each pair spaced apart longitudinally of said row a distance substantially equal to and no greater than the space between such blades of each vane at a point intermediate the longitudinally extending edges thereof;

(b) the portion of said sheet between the slots of each pair projecting to one side of said sheet to provide a bridge extending transversely of said sheet having opposite edges forming one of the edges of each slot;

(c) the said slots of each of said pairs thereof being adapted to receive therein the end edges of the blades of each, vane with said bridge projecting between the end marginal portions of said blades at their ends whereby said end marginal portions will project past said opposite edges of said bridge to the opposite side thereof for bending at least one of said last mentioned marginal portions over said sheet along one of said slots.

2. In a rail as defined in claim 1:

(d) one of the edges of each slot being arcuately curved to substantially correspond to the different arcuate curvatures of said blades.

3. In a rail as defined in claim 1:

(d) said sheet having parallel side edges, and

(f) said row of slots being the only slots in said sheet for the blades of the vanes and being positioned substantially centrally between said side edges;

(e) the marginal portions of said slots along the edges thereof that are opposite to the edges carried by said bridge projecting to the same side of said sheet as said bridge, whereby the said end marginal portions on such blades may be bent over the marginal portions of said sheet along either side of each slot as desired.

4. In combination with a double vane comprising a pair of parallel strips having parallel longitudinally extending side edges secured together and similarly curved transversely thereof about different arcs providing an inner blade and an outer blade with the arc of the inner blade being flatter than the arc of the outer blade whereby said blades will be spaced between their side edges with the outwardly facing surface of the inner blade of said vane being concavely curved in transverse cross-sectional contour and the oppositely outwardly facing surface of the outer vane being convexly curved in transverse crosssectional contour;

(a) a rail comprising a strip of sheet material;

(b) said rail being formed with a row of slots extending longitudinally of said strip, said slots being arranged in pairs spaced longitudinally of said strip and the spacing between the slots of each pair being equal to and no greater than the spacing between the blades of each vane, and the material of said strip along opposite edges of each slot projecting to one side of said strip;

(0) each of said vanes extending to said one side of said strip in a position substantially normal to the plane of the latter and the blades of each vane having end edges and marginal portions along the latter with said last mentioned marginal portions and end edges extending into and past a pair of said slots to the opposite side of said strip and bent over said opposite side of said strip along an edge of each slot for firmly securing each vane to such strip in said position.

5. The combination as defined in claim 4:

(d) said row of slots being in the central portion of said strip and said marginal portions of the blades that extend into the slots of each pair being substantially spaced between the longitudinally extending edges of each vane.

6. The combination as defined-in claim 4:

(d) the portion of said strip between each pair of slots providing a bridge extending transversely of said strip on which one of the said edges of the slots of each pair thereof are formed;

(e) the outer edges of the slots of each pair being arcuately curved linearly thereof to respectively follow and engage the arcuate cross-sectional contour of the convex surface of said outer blade and the concave surface of said inner blade.

References Cited UNITED STATES PATENTS Re. 25,153 4/1962 Speiser 13839 2,297,979 10/1942 Peck 138-39 2,884,956 5/1959 Perlin 138-39 2,972,358 2/1961 Hinden 13838 LAVERNE D. GEIGER, Primary Examiner.

B. KILE, Assistant Examiner. 

